Roll dampening

ABSTRACT

This invention relates to a car body roll controlling method wherein a car body roll is controlled by using a plurality of rows and steps of supply and exhaust valve means and any number of rows and steps of supply and exhaust valve means can be operated in response to the magnitude of the lateral acceleration acting parallel with the car body floor so that a proper control may be always made without causing hunting or the like.

United States Patent Shirane et al.

[451 Oct.31,1972

[54] ROLL DAMPENING 2,353,503 7/1944 Rost et a1 ..280/112 A Inventors: Yasuhior Shirane, Nishi omiya; voeltman et a1 Junzo Yamada Osaka both of 3,486,466 12/1969 Rodgers ..105/199 A J 3,572,747 3/1971 Pollinger et a1. ..105/197 B apan [73] Assignee: Sumitono Metal Industries Limited, Primary Examiner-Gerald M. Forlenza Osaka, Japan Assistant Examiner-J-loward Beltran Filed: O 16, 1970 Attorney-Watson, Cole, Grindle & Watson [21] App1.No.: 81,322 [57] ABSTRACT This invention relates to a car body roll controlling [30] Foreign A li fi priority Data method wherein a car body roll is controlled by using a plurality of rows and steps of supply and exhaust Oct. 18, 1969 Japan ..44/83516 valve means and any number of rows and steps of supply and exhaust valve means can be operated in US. Cl. ..188/33, 5/ 164, 10 response to the magnitude of the lateral acceleration l05/ 97 B, 199 199 acting parallel with the car body floor so that a proper 188/177 control may be always made without causing hunting [51] Int. Cl. ..B6lh 9/04, B61h 11/00, B6lh 13/00 or the like. [58] Field of Search ..105/164, 176, 199 A, 197 B, 105/199 R, 210; 280/112 A; 188/33, 177

I 8 D F [56] References Cited 3C 'awmg UNITED STATES PATENTS 2,135,224 11/1938 Schoepfet a1. ..105/164 I I l I B a, I

t I. I

PATENTEDnma: I972 3,701 397 SHEET 2 0F 4 I CENTRIFUGAL ACCELERATION CONTROL ELEMENT LQ EA A EL ATION 1 SAAB TEA EEA l FLOOR [BODY FLOOR DETECTOR FEED BACK ELEMENT CENTRIFUGAL ACCELERATION CONTROL ELEMENT\ Assam.

CAR know) AIR BODY mRAL L E L SPRING H J I FLOOR BODY FLOOR DETECTOR FEED BACK ELEMENT minimum I 12 3,701.39?

SHEET 3 OF 4 Fl G. '5

(g/sec.)

FIG..4B3.

INVENTOR.

. TE'NTEI'JIIIII a I I972 3. 701 397 SHEET II 0F 4 sec COEFFICIENT OF DISCHARGE (LATERAL ACCELERATION ,8 PARALLEL WITH CAR BODY FLOOR) FIG. 6

I'IIIIIII I CONTROL PRIOR ART 5 O t g gg EXHAUST OF SPRING No.I

8r? I t SUPPLY OF SPRING No.I

I BO A t H14 EXHAUST 0F SPRING No.I

' SUPPLY OF SPRING N0.I

I30! PRESENT W INVENTION EXHAUST 0F SPRING No.I

at SUPPLY OF SPRING NO.|

ROLL DAMPENING This invention relates to a method of controlling car body rolls by adjusting the levels of air springs on the right and left of a car body so that no unpleasant lateral acceleration may be felt by passengers when the rolling I stock runs on a curved track.

In the case of reducing the lateral acceleration felt by passengers when the rolling stock runs on a curved track or the like by supplying or exhausting the air springs on the right and left of the car body, in controlling the air apparatus, from the viewpoints of the compressibility of air, air-tightness and simplicity of the apparatus, on ON-OFF control in more preferable than a proportional control.

In the drawings:

FIG. 1 is a schematicview of a cross-sectional elevation of a conventional rolling stock;

FIG. 2A is a block diagram showing a conventional automatic roll control system;

1 FIG. 2B is a block diagram of a conventional car body roll controlling apparatus;

FIG. 3 is a diagram showing the operation of a supply and exhaust valve with the variation of the lateral acceleration parallel with the car body floor of the same, FIG. 4A is a block diagram showing an automatic roll control system using the control element in accordance with the present invention;

FIG. 4B is a block diagram of a car body roll controlling apparatus in a embodiment of the present invention;

FIG. 5 is a diagram showing a coefficient of discharge with the variation of the lateral acceleration parallel with the car body floor in the same embodiment;

FIG. 6 is a diagram showing the relation between the lateral acceleration parallel with the car body floor and the operation of the supply and exhaust valve of the car body roll controlling apparatus.

As an example of a conventional method by the ON- OFF control, as shown in FIGS. 1 to 3, two right and left air springs 1 and 1' are provided in the bottom part B of a rolling stock H and are connected to an axle A of wheels W through a supporting means S.

In the conventional car body roll controlling apparatus, as shown in FIGS. 2 and 3, electromagnetic air supply valves 2 and 2' are provided between the right and left air springs 1 and 1 and an air reservoir 6 and electromagnetic air supply valves 3 and 3' are provided between said air springs and the atmosphere so that, when the lateral acceleration parallel with the car body floor exceeds a fixed valve Bd, the electromagnetic air supply valve 2 on one side and the electromagnetic air exhaust valve 3' on the other side may be operated or, when it exceeds -Bd, the electromagnetic air supply valve 2' and the electromagnetic air exhaust valve 3 may be operated to roll the car body in a direction in which the acceleration parallel with the car body floor is canceled.

In such case, the amount of the air flow rate per unit time is adjusted with the effective orifice diameter of the electromagnetic valve or separately provided throttling orifices 4, 4', 5 and 5'. The orifice diameter is so important to the control and the moment of inertia of the car body or the time lag of the control is so closely related with it that, if the orifice diameter is small to ob tain a small coefficient of discharge, the objective control at the time of a high speed is insufficient to reduce the lateral acceleration parallel with the car body floor. If the orifice diameter is made large to obtain a large coefficient of discharge, when the lateral acceleration parallel with the car body floor is small, for example, when passing on a curved track at a low speed, an over control is caused and a reverse control for reversely pulling back the car body is made, this is repeated, a socalled hunting phenomenon is likely to occur and the car body becomes unstable. Further, on a curved track or the like, the radius of curvature, cant and running velocity are so variable that it is impossible to satisfy the conditions in any case.

As in the control example shown in FIG. 6, generally, in the case of passing on a curved track, as shown in I, a lateral acceleration (11. parallel with the track level plane acts and, when the orifice diameter is small, as shown in II, FIG. 6, the lateral acceleration 6 parallel with the car body floor remains so that the proper control has not been effected. (Ideally B is continuously zero.) 7 represents a supply or exhaust signal for the air spring on the right side. Those above the center line are supply signals. On the contrary, when the orifice diameter is large, as shown in III, FIG. 6, an over control is caused and so-called hunting state, in which a useless supply and exhaust are repeated, is made.

As mentioned above, the case of an ON-OFF control with the conventional control apparatus, if the orifice diameter is small, the controllability is low but, if the orifice diameter is large, the car body is likely to hunt and becomes unstable. In the present invention, in order to eliminate such defects, air supplying and exhausting electromagnetic valves are respectively arranged parallel so that, when the control quantity of the lateral acceleration parallel with the car body floor is small, the operating supply and exhaust valves may be few. On the other hand, when, the control quantity is large, the operating supply and exhaust valves may be many, thus a multistage control may be made, hunting may be difficult to cause and a stable and sufficient control may be made in the improvement. FIG. 2A shows, in block diagram, the arrangement of the car body floor with the conventional control element of FIG. 3.

An embodiment of the present invention shall be explained in the following with reference to the drawings. FIG. 4 shows an example of a control with three-row three-step electromagnetic valves. Electro magnetic air supply valves 2 2, and 2; are provided in parallel between an air spring 1 and an air reservoir 6 and electromagnetic air supply valves 2' .2, and 2', are provided in parallel between an air spring 1' and the airreservoir 6. Electromagnetic air exhaust valves 3,, 3, and 3, are provided between the air spring 1 and the atmosphere and electromagnetic air supply 3' 3', and 3'; are provided between the air spring 1'. and the atmosphere. These electromagnetic air supply and exhaust valves have such effective orifice diameters as can not be well controlled at the time of a high speed of the rolling stock with a single row or are throttled with i 1, s, s '1, '2 's, n 5. s '1 's and so as not to be controllable enough at the time of a high speed with a single row.

Now, as shown in FIG. 5, the dead zones of the quantity of the lateral acceleration parallel with the car body floor for the respective electromagnetic valve shall be I fld, I I fid, I I Bd I When a lateral acceleration parallel with the car body floor and larger than I [3d,l but smaller than I pd, l is applied, a single row of the supply and exhaust valves 2, and 3', or 3, and 2, is operated. When a lateral acceleration parallel with the car body floor and larger than I Bd l but smaller than I Bd I is applied, two rows of the supply and exhaust valves 2,, 2,, 3' and 3', or 3 3 2, and 2' are operated. Then, in the same manner, when a lateral acceleration parallel with the car body floor and larger than] fid l is applied, three rows of the supply and exhaust valves are operated.

Therefore, in response to the magnitude of the lateral acceleration acting parallel with the car body floor, any number of parallel rows of the supply and exhaust valves are operated to control the car body. Therefore, when the lateral acceleration parallel with the car body floor is small, air is supplied or exhausted so that no hunting will result. When such large control as at the time of a high speed is required, sufficient air is supplied and exhausted and a stable control high in the controllability can be made.

FIG. 4 shows, in block diagram, the arrangement of the car body floor with the control element of the present invention depicted in FIG. 5. present invention The result of making a two-row and two-step control by embodying the present invention is shown in IV in FIG. 6. When this result is compared with that of the conventional method, the superiority in the controllability can be made.

FIG. 4 shows, in block diagram, the arrangement of the car body floor with the control element of th present invention depicted in FIG. 5.

The result of making a two-row and two-step control by embodying the preseninvention is shown in IV in FIG. 6. When this result is compared with that of the conventional method, the superiority in the controllability can be appreciated and it can also be seen that all the problems in the conventional single row control are improved and that a sufficient effect is developed.

The more parallel rows and steps of the air supplying and exhausting electromagnetic valves, the more advantageous the control but the more complicated the apparatus, structure and maintenance. Therefore, two to four rows of two to four steps are practical. Further, the lateral accelerations parallel with the car body floor 3d,, 8d,, Bd, may be at irregular spacings. For example, the logarithmically larger the accelerations, the smaller the spacings: The respective orifice diameters may not be the same but may be different in consideration of the air reservoir, air springs and pressure difference from the atmosphere.

The comparisons of an embodiment of the present invention and an embodiment of the conventional technique with each other are shown in the following table.

Number Orifice diameter and of coefl'rcient of Control- Drawing steps discharge led state 1 Imm. (.03937 in.) (10 g/sec.) No hunt- FIG. 6

mg The correspond FIG. 6 III FIG. 6 IV In the present invention, as mentioned above, the car body roll is controlled by using a plurality of rows and steps of electromagnetic air supply and exhaust valves. Any number of rows and steps of air supplying and exhausting electromagnetic valves can be operated in response to the magnitude of the lateral acceleration acting parallel with the car body floor and therefore a proper control can be always made without causing hunting or the like. The terms rows and steps referred to throughout the specification indicate a sequential operation for the supply and exhaust valve means.

What is claimed is:

v l. A method of controlling roll dampening in a car for reducing lateral acceleration felt by passengers while the car body is travelling on a curved track by supplying and exhausting the air spring means to adjust the levels of the right and left air springs, comprising arranging a plurality of supply and exhaust valve means which are sequentially operated between the air springs and an air reservoir and between the air springs and the atmosphere and an ON-OFF means, controlling the coefficients of the discharge rate of said supply and exhaust means so that, when the degree of the lateral acceleration applied parallel with the car body is small, said coefficients of discharge rate may be small but, when the degree of lateral acceleration is large, said coefficients of discharge rate may be large and a sufficient controllability may be effected to prevent hunting of the bogie.

2. A car body roll controlling method according to claim 1 wherein an electromagnetic valve is used for the valve means.

3. A car body roll controlling method according to claim 1 wherein the said supply and exhaust valve means operate at a lateral acceleration parallel with the car body floor firstly of from 0.005 to 0.0l5g., secondly of from 0.01 to 0.03g., thirdly of from 0.015 to 0.03g., and fourthly of from 0.02 to 0.06g.

l 1 i i 

1. A method of controlling roll dampening in a car for reducing lateral acceleration felt by passengers while the car body is travelling on a curved track by supplying and exhausting the air spring means to adjust the levels of the right and left air springs, comprising arranging a plurality of supply and exhaust valve means which are sequentially operated between the air springs and an air reservoir and between the air springs and the atmosphere and an ON-OFF means, controlling the coefficients of the discharge rate of said supply and exhaust means so that, when the degree of the lateral acceleration applied parallel with the car body is small, said coefficients of discharge rate may be small but, when the degree of lateral acceleration is large, said coefficients of discharge rate may be large and a sufficient controllability may be effected to prevent hunting of the bogie.
 2. A car body roll controlling method according to claim 1 wherein an electromagnetic valve is used for the valve means.
 3. A car body roll controlling method according to claim 1 wherein the said supply and exhaust valve means operate at a lateral acceleration parallel with the car body floor firstly of from 0.005 to 0.015g., secondly of from 0.01 to 0.03g., thirdly of from 0.015 to 0.03g., and fourthly of from 0.02 to 0.06g. 